FGasper / gawk-web

GNU AWK compiled for web use.

gawk-web: GNU AWK for the Web

This package builds GNU AWK to WebAssembly and JavaScript via Emscripten.

Usage:

const gawk = require('./gawk.js');

// "barbaz\n23\n"
gawk().then( gawk => {
    console.log(
        gawk(
            ["foo bar baz", "1 2 3"].join("\n"),    // the text to process
            "{print $2 $3}",                        // your AWK code
        ),
    );
);

Specifically: require() returns a single function. When called, that function compiles AWK and returns (via a promise) a function that actually runs AWK. You can call that function over & over.

The above tracks closely with typical command-line usage:

{ echo foo bar baz; echo 1 2 3 } | awk '{print $2 $3}'

Notes

• Be sure to initialize the submodules (e.g., git clone --recurse-submodules) when cloning this repository.

• This build optimizes for ease of use by packing the WebAssembly into the JavaScript file. You can shrink the output significantly by removing the SINGLE_FILE flag from the build (see the Makefile). You’ll need to grab gawk.wasm from the gawk directory and ensure that it’s available wherever your gawk.js runs.

• This copies a number of usage patterns from jq-web.

• GNU AWK’s build seems to give the LDFLAGS twice when building. For us that causes pre.js and friends to be included twice. To work around that, those files eschew root-level let and const in favor of var.